CodeMirror.defineMode("pascal", function (config) {
    function words(str) {
        var obj = {}, words = str.split(" ");
        for (var i = 0; i < words.length; ++i) obj[words[i]] = true;
        return obj;
    }

    var keywords = words("and array begin case const div do downto else end file for forward integer " +
        "boolean char function goto if in label mod nil not of or packed procedure " +
        "program record repeat set string then to type until var while with");
    var atoms = {"null": true};

    var isOperatorChar = /[+\-*&%=<>!?|\/]/;

    function tokenBase(stream, state) {
        var ch = stream.next();
        if (ch == "#" && state.startOfLine) {
            stream.skipToEnd();
            return "meta";
        }
        if (ch == '"' || ch == "'") {
            state.tokenize = tokenString(ch);
            return state.tokenize(stream, state);
        }
        if (ch == "(" && stream.eat("*")) {
            state.tokenize = tokenComment;
            return tokenComment(stream, state);
        }
        if (/[\[\]{}\(\),;\:\.]/.test(ch)) {
            return null
        }
        if (/\d/.test(ch)) {
            stream.eatWhile(/[\w\.]/);
            return "number";
        }
        if (ch == "/") {
            if (stream.eat("/")) {
                stream.skipToEnd();
                return "comment";
            }
        }
        if (isOperatorChar.test(ch)) {
            stream.eatWhile(isOperatorChar);
            return "operator";
        }
        stream.eatWhile(/[\w\$_]/);
        var cur = stream.current();
        if (keywords.propertyIsEnumerable(cur)) return "keyword";
        if (atoms.propertyIsEnumerable(cur)) return "atom";
        return "word";
    }

    function tokenString(quote) {
        return function (stream, state) {
            var escaped = false, next, end = false;
            while ((next = stream.next()) != null) {
                if (next == quote && !escaped) {
                    end = true;
                    break;
                }
                escaped = !escaped && next == "\\";
            }
            if (end || !escaped) state.tokenize = null;
            return "string";
        };
    }

    function tokenComment(stream, state) {
        var maybeEnd = false, ch;
        while (ch = stream.next()) {
            if (ch == ")" && maybeEnd) {
                state.tokenize = null;
                break;
            }
            maybeEnd = (ch == "*");
        }
        return "comment";
    }

    // Interface

    return {
        startState: function (basecolumn) {
            return {tokenize: null};
        },

        token: function (stream, state) {
            if (stream.eatSpace()) return null;
            var style = (state.tokenize || tokenBase)(stream, state);
            if (style == "comment" || style == "meta") return style;
            return style;
        },

        electricChars: "{}"
    };
});

CodeMirror.defineMIME("text/x-pascal", "pascal");
